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u‰‰‘è–ÚF@High-Pressure Phase Transitions of Low-Coordination Oxides
u@Žt F@Prof. Karl Syassen
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The combination of high-resolution synchrotron x-ray diffraction, optical
spectroscopies, and large hydrostatic pressures produced by diamond anvil cells
offers a unique approach to studying structural, vibrational, and band structure
related properties of solids. Since the introduction of the DAC, high pressure
investigations of oxide materials have remained at the forefront of experimental
high pressure research. This talk will be concerned with recent pressure studies
of phase transitions in oxides [1-4] which have in common a low coordination of
their ambient pressure phases. Topics to be discussed are the rich PT phase
diagram of the spin-Peierls compound CuGeO$_3$ and new insights into
pressure-induced amorphization of berlinite-type compounds, as obtained from
combined x-ray diffraction, optical spectroscopy and Moessbauer studies.
[1] A. R. Goni et al., Phys. Rev. Lett. 77, 1079 (1996).
[2] S. Braeuninger et al., Phys. Rev. B 56, R11357 (1997).
[3] M. P. Pasternak et al., Phys. Rev. Lett. 79, 4409 (1997).
[4] T. Zhou et al., Phys. Rev. B 57, Jan. 1, 1998.
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Tel: 011-706-6929 Fax: 011-717-9304
E-mail: jun@phys.sci.hokudai.ac.jp
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